Means for electrolytic production of gases



Feb. 21, 1933.

0. K. ENZOR 1,898,352

MEANS FOR ELECTROLYTIC PRODUCTION OF GASES Filed May 51, 1952 2Sheets-Sheet l Attorne 7 Feb. 21, 1933. 0. K. ENZOR MEANS FORELECTROLYTIC PRODUCTION OF GASES' Filed May 51, 1932 2 Sheets-Sheet 2 x2 w l Ill.

Patented Feb. 21, 1933 UNITED STATES PATENT oFFlca A K- ENZOR, F I DIANALIS, NDIANA A SE QB 0F QNE-FQUB H D HOWA D DQB E Q N I APQL1S I DIAN 7eans roe nrncrnorv'rro rnopuc'r on or asses Application filed May 31,

This invention relates to means for producing the gases hydrogen andoxygen by an electrolytic cell and has for one of its pri mary objectsthe formation of a multiple cell unit without packing between thevarious cells and in which the separators and electrodes may beinstalled and removed. Another primary object of the invention is toprovide a permanent outside-shell and permanent gas partitions withinthe shell Within and between which the electrodes and separators may beremovably placed.

A still further important object of the invention is to provide meansfor supporting electrodes within the individual cells of the unit whichsupports may be carried through the bottom of the unit without danger ofleakage of the electrolyte and at the same time be of such nature thatthe electrodes may be in,- stalled and removed without dilflculty. Astill further important object of the invention is to provide means forautomatically maintaining a predetermined level of electrolyte withinthe unit dependent upon the pressure maintained in the take-off lines.

An advantage of the invention to be noted is that of the constructionwhereby a plurality of likemembers may be assembled one against theother to form the desired number of cells in any one unit with a commonfloor across the bottom of these members, which floor may be preformedto carry sleeves to receive the electrodes with definite spacing.

These and many other objects and advantages will become apparent tothose versed in the art from the following description of the inventionwhich is more or lessdiagrammatically illustrated by .the accompanyingdrawings, in which Fig. 1 is a fragmentary front elevation of a unitembodying the invention; i

Fig. 2, a fragmentary top plan view of the unit;

Fig. 3, a fragmentary end elevation of the unit on an enlarged scale;

Fig. 4, a detail in vertical section on an enlarged scale of anelectrode support, and

Fig. 5, a front view in perspective of an individual cell formingmember.

Like characters of reference indicate like 1932. Serial N0. 614,379.

parts throughout the several views in the drawings.

The present form of the invention involves the use of an eighteenpercent-solution of sodium hydroxide within which are immersed a numberof plate-like electrodes of substan-; tially pure iron and of nickel orof nickel plated" iron. 'In the present form as herein shown anddescribed, a unit is built up to include a number .of individual cellsnine in CC number although this number may be varied as desired and anynumber of the units may be hooked together to form a battery.

A number of cell defining members 10, Fig.

5, are formedto have a vertically disposed CE back wall 11 from the sideand top edges of which extends the flange 12 a distance equal to thedesired thickness of the individual cell. Angle bars 113 and 14 arebrought up by their ends against the under edge" of the '1 wall 11 tohave the legs of the bars turned respectively to have one leg serve as acontinuation of the flange 12 and the other legto be in the plane of thewall 11. The bars 13 and 14 are butt welded in this position to form anintegral structure wherein an open.- ing is provided between the bars 13and 14 below the wall 11. A gusset 15 is welded in place in the cornerbetween the under side of the wall 11 and the inturned leg of each barto serve in part as a reenforcing member. The width of the forwardlyturned leg of each bar 13 and 1a is the same as that of the flange 12.In the present form, eight of these members 10 are brought together tohave the 35 forward edges of the'flange 12 and :bars 13 and 14 abutt-heback of the next adjacent member and the members are welded one to theother about their 'lines'of contact to form a rectangular box-likestructure as viewed from the outside but divided internally into anumber of upper chambers between the various walls ll'closed around thesides and top but open from the under side, and having an open spaceentirely therethrough below the under edges of the walls 11.

A back member 1-6 is formed to have the same dimensions as that of themember 10 but in this member 16 there is no openingleft through the wallbetween the side flanges but instead this back wall extends integrallyfrom top to bottom and from side to side between side and top flanges.This member 16 is brought up to have its forwardly projecting flangeabut the back of the last member 10 and is welded thereto entirelyaround the contacting flange edge. A front member 17 is formed to besubstantially identical to the member 10 with a transverse upper wall 11and this member 17 is reversed in position as compared to that of eachmember 10 so as to have the edge of its then rearwardly turnedsurrounding flange abut the forwardly projecting flange about the frontmember 10 and is welded thereto about the line of contact.

A bottom enclosing floor 18 is formed, preferably out of heavier metalthan that of the other members 10 16 or 17, and is perforated with aplurality of staggered holes within each of which holes is inserted thelower end of a thimble 19 to have the lower end thereof come flush withthe under side of the floor. Each thimble is welded to the floor to forma gas and water tight joint therewith. The floor 18 is so perforated asto carry the thimbles 19 in fore and aft rows to have the thimblesalternately disposed to have transverse rows of thimbles come a sli htdistance in front of the forward sides of planes extended downwardlyfrom the walls 11 when the plate 18 is brought up against the undersides of the bars 13 and 1 1-. This floor 18 is rectangular in shape andis of sufiicient area to have its edges come out flush with the outersides of the side walls as defined between forwardly turned legs of thebars 13 and 14 and also to come flush with the outside of the back wallof the member 16 and across between the forward sides of the lower endof the member 17. The floor 18 is welded ontirely around its outer edgeto the members thereabove to form a gas tight oint therebetween.

Vith the unit thus assembled as above described, there is an openingleft through the front side or section 17. The various electrodes andseparators are carried into the unit through this opening. All of theelectrodes are of the same areaand each comprises a relatively thickflat iron plate rectangular in shape and havin supporting studs 20 fixedalong the lower edge. The positive electrodes 21 are nickel platedwhereas the negative electrodes 22 are left unplated with the ironsurfaces exposed. The area of each of these various electrodes issomewhat less than that of the opening through the front section 17 sothat the electrodes may be easily carried through this opening and backthrough the unit. The supporting studs 20 each have a head 23 which isslotted to receive the lower edge of the electrode therethrough and thehead is welded to the electrode. One of the negative electrodes 22 isfirst inserted through the opening in the section 17 and the upper edgeof the electrode is inserted to between the back wall 16 and the shortwall 11 immediately there in front so that the electrode may be liftedvertically to have the studs 20 raised up and allowed to drop downthrough the thimbles 19 which are disposed in a transverse linethereunder. An insulating collar 24, Fig. 4, is first placed over eachof the thimbles 19 to have the studs 20 passed therethrough so that theunder side of each head 23 may rest on the collar 24, the under side ofthe collar being supported by the top edge of the thimble. The underside of the head 23 is provided with an annular rib 25 and the top edgeof the thimble 19 is provided with a similar annular rib 26. Aninsulating sleeve 27 is slipped up over each stud 20 from the under sideof the floor 18, an insulating collar 28 brought up around the stud anda retaining nut 29 screw-threadedly engaged on the lower end of the studwhereby the tightening of the nut against the collar 28 will pull thestud 20 downwardly to cause the ribs 25 and 26 to become embedded in thecollar 24: so that a water tight oint is formed between the head of thestud and the thimble. The length of the sleeve 27 is such that itsrespective ends may come within cup-like depressions in the collars 24:and 28 but will not compressively be engaged by its ends therebetween sothat the collar 24L may be brought down against the upper end of thethimble 19 without being held thereaway by the sleeve. Preferably adrain passage 30 is provided through the lower collar 28 as anindicating means to determine from the outside if any leakage isoccurring about the collar 24 to within the thimble 19. Since theelectrode carried by the studs is xed across the head thereof, theelectrode will be securely held in averticalposition when the nuts 29are drawn up on the studs 20. Upon the placing of the back electrode 22as above indicated, an electrolytic mat or separator 31 made out of theusual and well known woven asbestos material is carried through theopening through the section 17 to have its upper edge brought againstthe front side of the wall 11 which is the first wall in front of theelectrode just placed. A clamping band 32, essentially U-shaped isbrought against the front of the mat and cap screws 33 are insertedthrough the band 32 and the mat 31 to screw-threadedly engage with thewall 11 horizontally thereacross and also vertically down along each ofthe inturned flanges of the bars 13 and 14 which are in the same planeas that of the wall 11 above. The mat 31 while being of a greater-areathan that of the electrodes is cut off across its bottom edge to leave aclearance or opening thereunder. After the mat 31 has been placed andsecured as above described, the next electrode, being a positive andnickel plated electrode 21 is then carried through the opening in thesection 17 to have its upper edge carried first upwardly to between thenext adjacent pairs of walls 11 to allow the studs extending from itslower edge to be entered into and dropped down through the thimbles 19extending in the row thereunder. The insulating end joint forming collar24 is employed as above indicated together with the sleeve 27, the lowercollar 28 and the nut 29. The collar 24 is preferably made out of somecompressible material such as rubber whereby the ribs 25 and- 26 may beembedded therein upon application of pressure. The insulating sleeve 27may be made of any insulating material even including porcelain sincethere is no strain upon it and it merely serves to space the studlaterally of the wall of, the thimble 19. The lower collar 28 is hereshown as being made of rubber although it may be made of any otherinsulating material even that which is not compressible. Since theelectrolyte is a solution of sodium hydroxide the upper collar 24 mustbe made out of material that is not affected by the caustic.

In the same manner additional electrodes 21 and 22 with the interveningmats are placed within the unit and secured in place whereby there arein the form illustrated five negative electrodes 22 and four positiveelectrodes 21 with a mat 31 between each of the adjacent electrodes.Preferably the upper edges of each of the electrodes is supportedagainst fore and aft displacement by insulating blocks 34 which areslipped loosely over the top edges of electrodes and are insertedupwardly between the back of the respective wall 11 and in front of themat retaining band 32.

After all of the electrodes and mats have been positioned and secured inplace within the unit, a cover 35 is brought up over the opening throughthe front section 17 and a gasket 36, preferably made of rubber isplaced around the opening on the forward side of the wall so that thecover 35 may be compressively drawn against the gaslretand the frontface of the wall on the section 17 by means of cap screws 37 passedthrough a retaining band 38 which passes entirely around the outer edgeof the cover 35 on its forward face, through the cover 35 and gasket 36and screw-threadedly engaged through the wall of the section 17, Fig. 3.Thus it is to be seen that the only opening which had been left in theunit and appearing through the front wall of the section 17 iseffectively closed and sealed over by the cover 35 forming a water tightjoint against the wall of the section through the rubber gasket 36. Thelower end of the cover 35 is brought up against a bar 39 which is turnedupwardly from the floor 18 to form a face thereacross against which thegasket 36 may be compressed.

A manifold 40 is horizontally disposed across the upper side of the unitand is there supported by relatively short nipples 41, four in number,Fig. 3, each of which nipples forms a passageway from the compartments42 which compartments are found between the transverse adjacent walls 11immediately above and to either side of the positive electrodes 21, orin other words each nipple leads from the second, fourth, sixth andeighth compartments. A second manifold 43 is likewise horizontallydisposed across the top of the unit in parallel alignment with butspaced apart from the other manifold 40. This manifold 43 is supportedabove the unit by nipples 45, here shown as five in number, whichnipples provide passages from the first, third, fifth, seventh and ninthcompartment 44, the compartments 44 being above the negative electrodes22.

Above and across between the two members 40 and 43 is located aplate'46, from the un der side of which toward one end leads a pipe 47to connect with the manifold 40, and from the other side of which leadsa pipe 48 to connect with the manifold 43. Both of these pipes 47 and 48extend upwardly beyond the top side of the plate 46 for substantialdistances and cups 49 and 50 respectively are inverted to hang down overthe upper ends of the pipes to be held in fixed relation with the pipes.Both pipes are formed with outlets 51 whereby gases ac cumulating ineither or both of the manifolds 40 and 43 may escape upwardly throughthe pipes, out of the openings 51 to within the inverted cups.Surrounding the cup 49 is a cylinder 52 having its lower end fitted towithin the plate 46 and a cap 53 fitted over its upper end. Bolts 54passing down through the cap 53 and through the plate 46 compressivelydraw the cap 53 against the top of the cylinder and hold the cylinderagainst the plate 46 against displacement. This cylinder 52 may be madeout of any suitable material and if desirable for the purposes ofobservation may be made out of glass although metal may be employed. Theinternal diameter of the cylinder 52 is sufiiciently great to permit itto surround the cup 49 with an annular space therebetween so that gasesand liquids may flow freely upwardly and downwardly therebetween.

In the same manner a cylinder 55 is placed over and surrounding the cup50 to be held in place on the plate 46 by bolts through the cap 56. Bothof the caps 53 and 56 are provided with outlet nipples 57 and 58respectively. The plate 46 is provided with internal passageways 59 and60 leading respectively from under the lower ends of the cylinders 52and 55 to under a centrally disposed cylinder 61 which is mounted on theplate 46 between the other two cylinders and is open at both the top andbottomends. Up-

wardly extending balfles 62 and 63 are disposed across the respectivepassageways 59 and 60 below the cylinder 61 so that any flow throughthese two passageways is deflected upwardly rather than allowing theflow from each of the passageways to collide.

A tank 4 open at the top is carried by the plate 46 back of the centralcylinder 61 and a pipe 65 leads from the bottom of this tank around anddown the side of the battery unit to connect therewith to provide apassageway from the tank to within the unit to discharge therewithin ata point just above the floor 18. This pipe may have its dischargeconnection through the wall of the unit or the floor thereof at otherpositions, the essential location being below the tops of the electrodes21 and 22. The plate 46 has an internal passageway 66, Fig. 3, leadingrearwardly from under the cylinder 61 and a pipe 67 is carried by theplate to extend upwardly therefrom with its lower end intercepting thepassageway 66 and its upper end connected to and discharging to withinthe tank 6% at a distance considerably above the base of the tank.

Mounted on the upper end of the cylinder 61 is a bracket 68 whichrockably supports a lever 69, one end of which extends over and is bentdownwardly to within the tank 64: to have a float 7O fixed to its lowerend. The other end of the lever 69, comprising a relatively short arm ispivotally engaged with the stem 71 connected to a valve within the valvebody 72 whereby lowering of the float will cause the lever 69 to rockand lift the valve member and upward travel of the float will tend toseat the valve member. The valve body 72 has a discharge end directeddownwardly to within the cylinder 61 and also has an inlet pipe 73leading from some supply of distilled water (not shown). A pair ofrelief pipes 74 and 75 is provided, one pipe preferably leading from aspace between two mats 31 between which is located a negative electrode22 and the other pipe from between two mats between which is located apositive electrode 21. The pipes 7a and 7 5 both lead out through theside wall of the unit at points substantially on tl e line of the underedges of the walls 11. The pipes are turned upwardly to extend wellabove the top of the unit.

Connecting bars 76 and 7 7 are passed under the unit to connectrespectively fore and aft rows of the depending ends of studs 20 leadingfrom negative and positive electrodes and bus bars 78 and 79interconnect the respective members in such manner that the bus bar 78is connected only to those connecting members attached to negativeelectrode studs and the bus bar 79 connected to those connecting membersattached only to the connecting member 77 uniting the studs of thepositive electrodes.

In operating the unit above described, an

eighteen percent solution of sodium hydroxide in distilled water ispoured into the unit through the tank 64 until the solution reaches somesuch level as indicated within the unit in Fig. 3 wherein the level isabove the under edges of the walls 11 completely submerging theelectrodes and mats and leaving a gas collecting space between each ofthe walls 11 thereabove. The bus bars 78 and 79 are connected in acircuit with some suitable supply of electrical energy whereuponhydrogen gas will become liberated along the negative electrodes 22 topass up through the electrolyte and oxygen will be formed along thepositive electrodes 21 to likewise pass up through the electrolyte, eachgas being kept entirely separate and prevented from mixing with theother by reason of the intervening mats 31 between electrodes.Consequently the respective gases hydrogen and oxygen will pass upthrough the electrolyte to escape to within the spaces thereabovebetween the walls 11 and flow out into the manifolds 1-3 and 10respectively, from which manifolds the gas flows upwardly through thepipes 48 and 47 to escape to within the inverted cups 50 and 49. Howeverbefore the are started to be generated, the tank 64 being initiallyempty, d stilled water allowed to flow past the valve member in the body72 to within the cylinder 61, and this cylinder being open from the topend as well as at the bottom end, the water will flow transversely fromthe bottom and through the passageways 59 and 60 to within both of thecylinders and 55. Continued flow from the Valve member 72 to within thetank 61 will raise the level of the water therewi hin as well as the twoadjacent cylinders to such a po nt that the water may travel upwardlythrough the pipe 67 to overflow into the tank 6%. As the gases aregenerated and flow within the cups 19 and 50, these gases will tend todisplace the water tl'ierewithin to bubble out around the lower edges ofthese cups to pass upwardly to within the cylinders 52 and 55 tending todisplace the water therewithin and to escape through the nipples 57 and58. As the gases are liberated sufficient pressure thereof upon theelectrolyte may be developed to lower the electrolyte level somewhat soas to force some of the electrolyte around up through the p pe 65 toenter within the tank 64 and thus raise the float 70 to shut off thesupply of distilled water. This pressure is determined by the locationof the upper outlet end of the pipe 6'? within the tank 6-1: since thedifference in level of the fluid in the tank 64 and the level ofelectrolyte in the unit determines the pressure exerted on the gaseswith n the chambers 42 and 44: and the level of the water within thecylinders 52 and is maintained substantially at the level of this outletand of the pipe 67 through the alternate lowering and raising of thefloat 70. Even after the valve member is seated generated in the unitunder pressure, and as in the body 72, the level of the water in thecylinders 52 and 55 will drop down to that of the outlet end of the pipe67 and at all times be suflicient to submerge the lower open ends of thecups 49 and 50. It is thus to be seen that both the hydrogen and oxygengases must pass out through distilled water from under the cups and thusbe washed before the gases pass out to the nipples 57 and 58. Should theflow from the nipples 57 and 58 be restricted unduly, suificientpressure may build up in the cylinders 52 and 55 to cause the gases todisplace the water within these two cylinders and allow the gases tofiow out through the passageways 59 and 60 and pass up through thecylinder 61 to escape into the atmosphere, the bafiies 62 and 68 tendingto prevent the intermixing of these gases as they pass up through thecylinder. Likewise should an excessive pressure be built up so as todepress the level of the electrolyte to below the under edges of thewalls 11 whereby there would be a tendency to uncover the upper ends ofthe mats 31, gases above the electrolyte would then escape through thesafety pipes 74: and 75, these pipes otherwise being filled withelectrolyte and acting as stand pipes within which the level isordinarily that within the tank 64. As the water of the solution may beused up, new distilled water is added through the action of the droppingof the float and this water enters through the cylinder 61 so that anytracesof caustic solution coming over with the gases and washed out inthe cylinders 52 and 55 will be returned to within the unit eventuallyas the water flows up around the pipe 67 into the tank 64 and downthrough the return pipe 65.

Thus it is to be seen that I have produced a battery unit built up froma number of cells into an integral structure wherein electrodes andseparators or mats may be installed and removed without having to breakjoints or make up joints between the individual cells; that theelectrical connections are made with the various electrodes from withoutthrough connections insuring loss of electrolyte through leakage; thathas an automatic control of the electrolyte level; and is fully providedwith safety features preventing the accumulation of gases beyond apredetermined pressure and preventing the formation of explosivemixtures. Combined with these structures and safety features is the factthat the gases are simultaneously washed as they leave the battery unitso that they are immediately available for use in other operationswherein a high degree of purity of gases is necessary.

Attention is directed to the fact that I em ploy a unit with closed topcells and by reason of the welding together of the cell walls to form anintegral structure, gases may be above indicated, that pressure iscontrolled by the level of liquids in the tank 61 as affected by thelevel of the outlet of the overflow pipe 67 By varying the outlet levelof the pipe 67, the pressure of the gases in the unit is accordinglyvaried. For example, gases may be generated in the unit at suflicientpressure to be conveyed directly to a welding or cutting torch withoutany intermediate compressor. V

While I have herein described and shown my inventionin the form as nowbest known to me, it is obvious that structural changes may be madewithout departing from the spirit of the invention and I therefore donot desire to be limited to that precise form except as maybe necessaryby the limitations imposed by the following claims.

I claim:

1. In a gas producing electrolytic device, a plurality of individualcell defining units, each of said units comprising a metallic wall witha forwardly turned flange around its. top and vertical edges and havingdownwardly extending legs from the sides thereof with forwardlyextending flanges, said units being assembled oneagainst the other tohave the flanges of one unit abut and be welded to the back of the nextforward unit to define an externally appearing box-like structurewith aplurality of chambers defined between said metallic walls, a backsection forming a back wall and a front section, each of said sectionsbeing welded to said box-like structure, said front section having anopening therethrough, a floor extending entirely across under and weldedto the lower ends of said sections and of the legs of said units, aplurality of thimbles carried by said floor'in transverse rows, positiveand negative electrodes, studs fixed to the lower edges of theelectrodes fitting withbelow said floor, said electrodes beingalternatingly disposed and each having a shape and area permitting it tobe inserted to through said front section opening and carried back intosaid box-like structure to enter. the studs into the thimbles',means'for making a water tight joint between the studs and the thimbles,mats hanging from said unit plates to between adjacent electrodes, amanifold interconnecting alternate chambers, a second manifoldinterconnecting the other chambers, and a cover over said front sectionopening secured to the section with a water-tight fit.

2. In a gas producing electrolytic device, aplurality of individual celldefining units, each of said units comprising-a metallic wall with aforwardly turned flange around its top and vertical edges and havingdownwardlyextending legs from the sides thereof with forwardly extendingflanges, said units being assembled one against the other to have theflanges of one unit abut and be welded to the back of the next forwardunit to define an externally appearing box-like structure with aplurality of chambers defined between said metallic walls, a backsection forming a back wall and a front section, each of said sectionsbeing welded to said boxlike structure, said front section having anopening therethrough, a floor extending entirely across under and weldedto the lower ends of said sections and of the legs of said units, aplurality of thimbles carried by said floor in transverse rows, positiveand negative electrodes, studs fixed to the lower edges of theelectrodes fitting within said thimbles and extending externally tobelow said floor, said electrodes being alternatingly disposed andeachhaving a shape and area permitting it to be inserted to through saidfront section opening and carried back into said box-like structure toenter the studs into the thimbles, means for making a water tight jointbetween the studs and the thimbles, mats hanging from said unit platesto between adjacent electrodes, a manifold interconnecting alternatechambers, a second manifold interconnecting the other chambers, and acover over said front section opening secured to the section with awater-tight fit, water containing cylinders individually connected withsaid manifolds, water sealed gas escape means interconnecting saidcylinders, an overflow tank interconnected with said means, and a drainfrom the tank connecting with said box-like structure below the saidunit walls.

3. In a gas producing electrolytic device, a plurality of individualcell defining units, each of said units comprising a metallic wall witha forwardly turned flange around its top and Vertical edges and havingdownwardly extending legs from the sides thereof with forwardlyextending flanges, said units being assembled one against the other tohave the flanges of one unit abut and be welded to the back of the nextforward unit to define an externally appearing box-like structure with aplurality of chambers defined between said metallic walls, a backsection forming a back wall and a front section, each of said sectionsbeing welded to said box-like structure, said front section having anopening there through, a floor extending entirely across under andwelded to the lower ends of said sections and of the legs of said units,a plurality of thimbles carried by said floor in transverse rows,positive and negative electrodes, studs fixed to the lower edges of theelectrodes fitting within said thimbles and extending externally tobelow said floor, said electrodes being alternatingly disposed and eachhaving a shape and area permitting it to be inserted to through saidfront section opening and carried back into said box-like structure toenter the studs into the thimbles, means for making a water tight jointbetween the studs and the thimbles, mats hanging from said unit platesto between adjacent electrodes, a manifold interconnecting alternatechambers, a second manifold interconnecting the other chambers, and acover over said front section opening secured to the section with awater-tight fit, water containing cylinders individually connected withsaid manifolds, water sealed gas escape means interconnecting saidcylinders, an overflow tank interconnected with said means, and a drainfrom the tank connecting with said box-like structure below the saidunit walls, valve means for admitting water to within said escape means,and a float in said overflow tank operating said valve means.

l. In an electrolytic device for producing gases, an integrally formedmetallic box-like unit having a plurality of transverse spaced apartwalls defining chambers in the upper part thereof, said wallsterminating to leave a clear opening from front to back in the unithaving a cross-sectional area exceeding the area of one of said walls,an opening in the front of said unit, a floor in said unit, a pluralityof thimbles fixed to the floor and disposed in transverse rows directlyunder said chambers, plates forming positive and negative electrodesalternatingly disposed fore and aft in parallel vertical alignment tohave their upper ends directed toward said chambers, studs fixed totheplates and inserted through said thimbles to extend externally to belowsaid floor, an insulating and sealing collar about each stud and the topend of the thimble, a mat secured to each of said transverse walls tohang between ad- 4 jacent plates whereby each of said chambers isextended downwardly to receive a plate therein, said mats terminating adistance above the said floor and being secured by their vertical edgesto flanges inturned from the side walls of said box-like structure, saidplates and mats being each of a shape and area to permit them to becarried through said front opening and fixed in position within theunit, a cover for said opening, and 5 5' gas collecting manifoldsinterconnecting alternate chamber 5. In an electrolytic unit forproducing gases in combination with a box-like structure carrying anelectrolyte, a plurality of electrodes therein with individual chamberswithin which the gases are produced, and a pair of manifolds collectingseparate gases from said chambers, a pair of cylinders, one cylinderbeing interconnected to one manifold and the other cylinder beingconnected to the other manifold. an inverted cup in each cylinder underwhich gases are discharged in flowing from the manifolds, each cylinderhaving an upper gas outlet, a third cylinder interconnected at thebottom from the bottoms of the other two cylinders by passageways, anoverflow tank, a drain pipe from the tank to said box-like structure,and an overflow pipe leading from a passage from the bottom of the thirdcylinder to discharge into the tank at a point spaced above the bottomthereof dependent upon the gas pressure to be maintained in saidstructure.

6. In an electrolytic unit for producing gases in combination with abox-like structure carrying an electrolyte, a plurality of electrodestherein with individual chambers within which the gases are produced,and a pair of manifolds collecting separate gases from said chambers, apair of cylinders, one cylinder being interconnected to one manifold andthe other cylinder being connected to the other manifold, an invertedcup in each cylinder under which gases are discharged in flowing fromthe manifolds, each cylinder having an upper gas outlet, a thirdcylinder interconnected at the bottom from the bottoms of the other twocylinders by passageways, an overflow tank, a drain pipe from the tankto said box-like structure, and an overflow pipe leading from a passagefrom the bottom of the third cylinder to discharge into the tank at apoint spaced above the bottom thereof dependent upon the gas pressure tobe maintained in said structure, a valve for admitting a fluid into saidthird cylinder, and float means in said tank for operating said valve.

7. In an electrolytic cell, in combination with an electrode and ametallic floor in the cell, a metallic thimble integrally joined withthe floor, a head stud fixed to the electrode and extending through thethimble externally of the floor, a head on the stud, an insulatingcollar on the stud under the stud head and resting on the top of saidthimble, said collar being slightly compressible, a rib around the underside of the stud head, a rib around the top edge of the thimble, saidribs becoming embedded in said collar upon drawing the stud down throughthe thimble, an insulating sleeve around the stud, a lower insulatingcollar around the stud under the 50 floor, and a nut screw-threadedlyengaging the lower end of the stud to compress the lower collar againstthe floor and pull down the stud.

8. In an electrolytic cell, in combination 55 with an electrode and ametallic floor in the cell, a metallic thimble integrally oined with Intestimony whereof I afiix my signature.

ORA K. ENZOR.

